About 30 mature Sumatran rhinos are estimated to be living in the wild.

A sanctuary in Indonesia is celebrating the birth of a Sumatran rhino, the most threatened species of rhinoceros in the world.

The healthy male calf was born on Saturday at the Sumatran Rhino Sanctuary at Way Kambas National Park in the Lampung province, the Indonesian government announced Sunday.

The baby rhino is the first for his mother, Delilah, as well as his father, Harapan, a male Sumatran rhino born at the Cincinnati Zoo, Indonesian Minister of Environment and Forestry Siti Nurbaya said in a statement.

Although Delilah is a first-time mom, she began nursing her calf immediately after he was born “with no fuss or fanfare,” Nina Fascione, executive director of the International Rhino Foundation, said in a statement.

“It’s an incredible event that gives hope to the future of this critically endangered species,” Fascione said.

The calf, whose name was not released, is the second to be born at the sanctuary in two months and the fifth birth at the sanctuary overall. Delilah herself was the second calf to be born at the sanctuary in 2016 and is now the first captive-born Sumatran rhino to give birth, officials said.

Sumatran rhinos are listed as critically endangered on the International Union for the Conservation of Nature’s Red List of Threatened Species. There are only about 30 mature Sumatran rhinos living in the world, all in Indonesia, and their population is decreasing, according to the IUCN.

The species is currently extinct in Bangladesh, Bhutan, Brunei, Cambodia, India, Laos, Malaysia, Thailand and Vietnam, according to the Red List. Their presence in Myanmar is currently uncertain.

Progress made in recent years is pointing toward the possible survival of the species, researchers said.

Two years ago, there was only one captive Sumatran rhino pair in the world able to successfully produce offspring, Fascione said.

Now, there are three pairs — six rhinos in total — who are proven breeders. This equates to “much better odds” for the long-term survival of the species, Fascione said.

“The Sumatran rhino breeding program has never been in a better position,” she added.

There are now 10 Sumatran rhinos living at the sanctuary, a semi-wild breeding and research facility managed by the Rhino Foundation of Indonesia, officials said.

Veterinarians and animal care staff will closely monitor Delilah and her calf while they bond, said Jansen Manansang, executive director of the foundation.

The goal of the breeding program is to eventually supplement the declining wild population of Sumatran rhinos, said Satyawan Pudyatmoko, director general of the Indonesian Ministry of Forest’s Natural Resources and Ecosystem Conservation. In the future, rhinos born at the sanctuary could be released back into their natural habitats, Pudyatmoko said.

“Going forward, the Rhino Foundation of Indonesia continues to be committed to assisting and fully supporting the programs and efforts of the Government of the Republic of Indonesia, especially in rhino conservation efforts in Indonesia,” Manansang said.